A 6 volt ignition system consisted of the following parts:
Wire from ign switch to coil
Ignition coil
wire from coil to points
points
condenser
distributor
When Chevy first went to 12 volts in '55, the engineers noticed that the coils and points were burning up quickly. They solved the problem by adding a resistor to the wire that went from the ign switch to the coil. This dropped the voltage down to about 7 or 8 volts at the coil, and kept it and the points from overheating.
The external resistor was then replaced with a resistance wire from the switch to coil. This wire had the resistance needed built into it, and thus eliminated the need for external resistor.
In later years, the resistor was built inside the coil. This eliminated the need for any external resistance. This "internal resistor coil" is a TRUE 12 volt coil, as it can be connected directly to the 12 volt ign switch.
When GM went to HEI in the mid '70s, the coils were redesigned to work with a solid-state trigger, different plug wires and larger plug gaps. The windings of these coils do not require a resistance, nor do they have one built-in. These coils cannot be used with points ignition, as they won't trigger correctly with points.
Short answer: I assume you're running a 6 volt system, so you don't need a resistor. Use a 12 volt coil for points ignition that does NOT have a built-in resistor. The system is already at 6 volts, so you can use your stock points and condenser.
The condenser is a special type of capacitor. It is for suppression of radio static and to reduce arcing and pitting of the points. When they fail closed-circuit, they can provide a coil a constant ground. This prevents the coil from firing, cuz the coil never "sees" the points open. If a condenser fails open circuit, it does not suppress radio noise, and the points pit and wear out quickly while running.
Good luck
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